It's part of the standard curriculum for the lower levels at my Japanese language school. I haven't actually used it myself, though, because I transfered in at a higher level.

From what I've seen/heard, it's a great book, but it's pretty intense. If you don't have a teacher forcing you through it or enough dedication to chew through it on your own (which means a lot of independantly looking up stuff you don't understand), then you might be better off with a book that has more thorough explanations in English.

alex, if boredom is a problem for you, minna no nihongo might not be a good selection for you. It will teach you lots of vocab and grammar, but the textbook isn't exactly "fun". Genki series is probably a much better choice if you want to enjoy your learning path. It has all the advantages of MNN and more, but only disadvantage is that MNN will get you farther along, since it has 50 lessons total versus Genki's 23 lessons. I think it's worth it though. Go to your local bookstore that carries the book and check it out. You'll see a big difference from JFBP.

ive decided to go for the minna no nihongo, i think i'd enjoy it. I choose against genki cos a few ppl i know that have gone through its course end up with asking 'whats next?!'
vocab and grammer is exactly what i want to improve on at the moment. Im just worried its gonna be a little slow learning new words from scratch in kana.

Well, if you also got the "english" corresponding book with the vocabulary and grammar, learning new words is not that difficult, since you have the corresponding vocabulary - and grammar - for each lesson.
To tell the truth, I find the pacing a little faster than JFBP, having done both, a few year apart. But it's quite different in what comes first...
Be sure to get the audio files! quite helpful; not the videos, since their contents are also in the audio files, except if you want a good laugh sometimes!

I know that 3A Network makes Minna no Nihongo and while I was in Japan it was a favorite among non native speakers of english (and also Japanese for busy people)

I talked to some people back here in the states and they like the Genki book although I don't think they have seen the Minna no Nihongo series. I've looked at both and I think they're are both good books BUT I'm biased towards 3A Network because of the Kanzen Masuta series that I used when studying for the JLPT last year.

Honestly a vocab list, some flash cards, and a sentence pattern dictionary (again my favorites are the kanzen masuta ones) will teach you alot more but you might skip out on a few things... I know I never used a real text book while learning Japanese and I cleped out of every college Japanese class they made a clep course for.